import java.util.*;
/**
 * Created with IntelliJ IDEA.
 * Description:
 * User: 晓星航
 * Date: 2023-04-07
 * Time: 19:27
 */
public class Java_b_xxh {

    public static String func(String str) {
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < str.length(); i++) {
            char ch = str.charAt(i);
            if(!sb.toString().contains(ch + "")) {
                sb.append(ch);
            }
        }
        return sb.toString();
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        while (scanner.hasNextLine()) {
            String str = scanner.nextLine();
            String ret = func(str);
            System.out.println(ret);
        }
    }

}
